{"id":1912,"date":"2022-06-22T10:30:34","date_gmt":"2022-06-22T10:30:34","guid":{"rendered":"https:\/\/csiag.eu\/?p=1912"},"modified":"2025-10-24T18:05:27","modified_gmt":"2025-10-24T18:05:27","slug":"water-disinfection-uv-c","status":"publish","type":"post","link":"https:\/\/csiag.eu\/en\/blog\/2022\/06\/22\/wasser-entkeimung-uv-c\/","title":{"rendered":"Water disinfection using UV-C"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_82_2 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of contents<\/p>\n<span class=\"ez-toc-title-toggle\"><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/csiag.eu\/en\/blog\/2022\/06\/22\/wasser-entkeimung-uv-c\/#Studien\" >Studies<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/csiag.eu\/en\/blog\/2022\/06\/22\/wasser-entkeimung-uv-c\/#Die_Theorie_%E2%80%A6\" >Theory \u2026<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/csiag.eu\/en\/blog\/2022\/06\/22\/wasser-entkeimung-uv-c\/#Strahlungs-Dosis\" >Radiation dose<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/csiag.eu\/en\/blog\/2022\/06\/22\/wasser-entkeimung-uv-c\/#%E2%80%A6_und_die_Praxis\" >... and the practice<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/csiag.eu\/en\/blog\/2022\/06\/22\/wasser-entkeimung-uv-c\/#Wahl_des_Einbauortes\" >Choice of installation location<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/csiag.eu\/en\/blog\/2022\/06\/22\/wasser-entkeimung-uv-c\/#Besonderheit_Druckpumpe\" >Special feature pressure pump<\/a><\/li><\/ul><\/nav><\/div>\n<span class=\"span-reading-time rt-reading-time\" style=\"display: block;\"><span class=\"rt-label rt-prefix\">Reading time<\/span> <span class=\"rt-time\"> 3<\/span> <span class=\"rt-label rt-postfix\">minutes<\/span><\/span>\n<p>Water disinfection can be carried out in various ways. The safest and simplest solution is irradiation with UV-C (wavelength 200 ... 280 nm). This method is used in laboratories, clinics, industry, aquariums and households alike. Microorganisms such as bacteria, viruses, yeasts and fungi are killed 99.9 % at a suitable flow rate per time unit and irradiation intensity.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Studien\"><\/span>Studies<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Among water specialists, UV-C purification is occasionally discussed with regard to the inactivation of viruses. The argument is that viruses are smaller than bacteria and would not be inactivated by UV-C.<\/p>\n\n\n\n<p>The <a href=\"https:\/\/www.sciencedirect.com\/science\/article\/pii\/S0043135424012211?via%3Dihub#bib0050\" target=\"_blank\" rel=\"noreferrer noopener\">Study situation<\/a> However, this confirms the inactivation, also of viruses, of course always depending on the dose rate.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Die_Theorie_%E2%80%A6\"><\/span>Theory \u2026<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>However, sterilization is not the same <a href=\"https:\/\/csiag.eu\/en\/reverse-osmosis\/\" data-type=\"post\" data-id=\"2131\">Filtering<\/a>. Contaminating particles are only removed using appropriate filters! In addition, contaminated water reduces UV-C transmission and thus the effectiveness of UV-C radiation.<br>For example, at a distance of 1 cm from the radiation source (corresponding to 80 % of the 100% radiation power, after 17 mm still 70 %) ultrapure water has a transmission of 99 .. 100 %, drinking water 85 .. 98 %, rainwater 75 .. 85 % and Wastewater 50 .. 75 %.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Strahlungs-Dosis\"><\/span>Radiation dose<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>The radiation dose is calculated from the time (<em>t<\/em>) multiplied by the intensity (<em>I<\/em>) of the UV-C lamp and is in mJ\/cm<sup>2<\/sup> measured.<\/p>\n\n\n\n<p>The dose required to kill microorganisms is, for example:<\/p>\n\n\n\n\n<table id=\"tablepress-1\" class=\"tablepress tablepress-id-1\">\n<thead>\n<tr class=\"row-1\">\n\t<th class=\"column-1\">pathogen<\/th><th class=\"column-2\">Dose mJ\/cm2<\/th>\n<\/tr>\n<\/thead>\n<tbody class=\"row-striping row-hover\">\n<tr class=\"row-2\">\n\t<td class=\"column-1\">Clostridium tetani<\/td><td class=\"column-2\">4,90<\/td>\n<\/tr>\n<tr class=\"row-3\">\n\t<td class=\"column-1\">Hepatitis A<\/td><td class=\"column-2\">11,00<\/td>\n<\/tr>\n<tr class=\"row-4\">\n\t<td class=\"column-1\">Infective pancreatic necrosis<\/td><td class=\"column-2\">60,00 *<\/td>\n<\/tr>\n<tr class=\"row-5\">\n\t<td class=\"column-1\">Klebsiella pneumoniae<\/td><td class=\"column-2\">11,00<\/td>\n<\/tr>\n<tr class=\"row-6\">\n\t<td class=\"column-1\">Legionella pneumophilla<\/td><td class=\"column-2\">2,04<\/td>\n<\/tr>\n<tr class=\"row-7\">\n\t<td class=\"column-1\">Poliovirus<\/td><td class=\"column-2\">12,00<\/td>\n<\/tr>\n<tr class=\"row-8\">\n\t<td class=\"column-1\">Pseudomonas aeruginosa<\/td><td class=\"column-2\">11,00<\/td>\n<\/tr>\n<tr class=\"row-9\">\n\t<td class=\"column-1\">Rotavirus<\/td><td class=\"column-2\">35,00<\/td>\n<\/tr>\n<tr class=\"row-10\">\n\t<td class=\"column-1\">Saccharomyces cerevisiae<\/td><td class=\"column-2\">6,00<\/td>\n<\/tr>\n<tr class=\"row-11\">\n\t<td class=\"column-1\">Salmonella typhi<\/td><td class=\"column-2\">14,00<\/td>\n<\/tr>\n<tr class=\"row-12\">\n\t<td class=\"column-1\">Salmonella typhimurium<\/td><td class=\"column-2\">13,00<\/td>\n<\/tr>\n<tr class=\"row-13\">\n\t<td class=\"column-1\">Spores of the bac. subtilis<\/td><td class=\"column-2\">12,00<\/td>\n<\/tr>\n<tr class=\"row-14\">\n\t<td class=\"column-1\">Staphylococcus aureus<\/td><td class=\"column-2\">36,00<\/td>\n<\/tr>\n<tr class=\"row-15\">\n\t<td class=\"column-1\">Streptococcus faecalis<\/td><td class=\"column-2\">4,50<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<!-- #tablepress-1 from cache -->\n\n\n\n<p>As a rule, the dose information for the devices is in J\/m<sup>2<\/sup> or mJ\/cm<sup>2<\/sup> specified. In terms of the designated effectiveness of at least 90% in killing bacteria and viruses, they refer to the respective flow rate.<\/p>\n\n\n\n<p>*Values above 40 mJ\/cm<sup>2<\/sup> require the use of a second equivalent stage for flow rates above 4 ... 7 liters\/min. require the use of a second equivalent stage in order to also reliably detect these pathogens, taking into account possible photoreactivation on the part of the photolyases. These enzymes may repair the cell damage to the DNA caused by the UV-C light. To counteract this effect effectively, doses of around 44 mJ\/cm<sup>2<\/sup>or 440 J\/m<sup>2<\/sup> necessary.<\/p>\n\n\n\n<p>Halving the flow rate results in a doubling of the dose, which in turn increases the disinfection capacity by a factor of 10. The 90 percent disinfection then increases to 99 %. Tripling the dose requires 99.9 % disinfection.<\/p>\n\n\n\n<p>This means that the above-mentioned photoreactivation at half the flow rate is already taken into account with one unit.<br>However, if you intend to sterilize highly contaminated water and require higher flow rates, you are well advised to use a second and possibly third stage.<br><br><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E2%80%A6_und_die_Praxis\"><\/span>... and the practice<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Pressure pumps installed in mobile homes, e.g <a href=\"https:\/\/www.amazon.de\/Shurflo-Wasser-Camper-Liter-Armaturen\/dp\/B07DYS5XZJ\/ref=sr_1_1?__mk_de_DE=%C3%85M%C3%85%C5%BD%C3%95%C3%91&amp;crid=22S8P4PJDEWEW&amp;keywords=shurflo+2095-204-112&amp;qid=1655889462&amp;sprefix=shurflo+2095-204-112%2Caps%2C123&amp;sr=8-1\" target=\"_blank\" rel=\"noreferrer noopener\">Shurflo<\/a>, deliver up to 7 liters\/min. One <a href=\"https:\/\/www.purion.de\/produkte\/purion-500\/\" target=\"_blank\" rel=\"noreferrer noopener\">Purway 500<\/a> UV-C sterilization system (12 or 24 V DC) is for up to 400 liters\/h at 400 J\/m<sup>2<\/sup> and operates at 254 nm with a UVT (<em>UV transmission<\/em>) of 90 %. The flow rate is 6.7 liters per minute. Due to the small pipe cross-sections of 10 ... 12 mm, the Purway system delivers a maximum of 1.1 liters\/min. This results in a dose of 6,666.67 J\/m at a flow rate of around 60 liters\/hour<sup>2<\/sup> and an efficiency of 99.999999999999 % (corresponding to log12)!<\/p>\n\n\n\n<p>It makes sense to install the system with a so-called monitoring unit. This warns when the lamp&#039;s service life has been reached in order to ensure a consistently high disinfection capacity.<br>It should be noted that the dose rate of the lamp decreases over time. Therefore, either the total dose rate should be oversized accordingly or a faster lamp replacement interval should be planned.<br>Alternatively, an operating hours counter can be installed if a system without a monitoring unit has been purchased.<\/p>\n\n\n\n<p>It is also advisable to order a replacement UV-C lamp. This is not so much with regard to the expected service life, but rather because of the highly probable premature failure at the worst possible time according to Murphy's law, far away from a supplier for the corresponding spare part ...<br><br><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Wahl_des_Einbauortes\"><\/span>Choice of installation location<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>You will not need germ-free water in the shower or bathroom. But probably in the kitchen. The cold water pipe just before the tapping point is therefore a good idea. There is usually enough space on the back wall of the sink cabinet to integrate the 32 cm long UV unit into the water hose.<\/p>\n\n\n\n<p>In addition to two matching hose nozzles and hose clamps, you also need a 12\/24 V DC connection. This is where the water pump comes in handy. A two-wire cable, laid along the water hoses towards the pump and connected there parallel to the power supply, is sufficient if a suction pump is activated via the tap.<br><br><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Besonderheit_Druckpumpe\"><\/span>Special feature pressure pump<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>For intermittently running pressure pumps, a delay circuit must be installed in parallel, which in turn takes over the power supply to the disinfection system so that it remains switched on for an adjustable period of time even after the pressure pump has been switched off and water extraction has been resumed.<br><br>This is accomplished by one <a href=\"https:\/\/www.amazon.de\/dp\/B07W6NLTYT\/ref=pe_27091401_487024491_TE_item\" target=\"_blank\" rel=\"noreferrer noopener\">Control electronics<\/a>, which delays the switching off of the supply voltage for the disinfection system for an adjustable period of time.<br>It is connected directly to the on-board voltage of 12 or 24 V. At the signal input, a cable is connected in parallel to the outgoing plus line of the pressure switch of the pressure pump. When the pump starts, the delay time is started by the activated plus level and the pressure pump is switched on and the disinfection system is kept switched on for the set period of time.<\/p>\n\n\n\n<div style=\"height:34px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p>ps If you need personal support in the implementation for a fee, you are welcome to&nbsp;<a href=\"https:\/\/csiag.eu\/en\/consulting-service\/\">Ticketing<\/a>&nbsp;make!<\/p>\n<\/blockquote>\n\n\n\n<p><br><br><\/p>","protected":false},"excerpt":{"rendered":"<p><span class=\"span-reading-time rt-reading-time\" style=\"display: block;\"><span class=\"rt-label rt-prefix\">Reading time<\/span> <span class=\"rt-time\"> 3<\/span> <span class=\"rt-label rt-postfix\">minutes<\/span><\/span>Water disinfection can be carried out in various ways. The safest and simplest solution is irradiation with UV-C (wavelength 200 ... 280 nm). This method is used in laboratories, clinics, industry, aquariums and households alike. Microorganisms such as bacteria, viruses, yeasts and fungi are killed 99.9 % at a suitable flow rate per time unit and irradiation intensity. Studies under...&nbsp;<a href=\"https:\/\/csiag.eu\/en\/blog\/2022\/06\/22\/wasser-entkeimung-uv-c\/\" rel=\"bookmark\">Read More \"<span class=\"screen-reader-text\">Water disinfection using UV-C<\/span><\/a><\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_lmt_disableupdate":"","_lmt_disable":"","neve_meta_sidebar":"","neve_meta_container":"","neve_meta_enable_content_width":"","neve_meta_content_width":0,"neve_meta_title_alignment":"","neve_meta_author_avatar":"","neve_post_elements_order":"","neve_meta_disable_header":"","neve_meta_disable_footer":"","neve_meta_disable_title":"","footnotes":""},"categories":[340,338],"tags":[680,691,684,687,618,591,688,693,679,696,694,697,695,686,698,689,690,699,685,683,682,681,677,678,676,692],"class_list":["post-1912","post","type-post","status-publish","format-standard","hentry","category-wasser-entkeimung-mittels-uv-c","category-wasser-management","tag-bestrahlungsintensitaet","tag-dna","tag-dosis","tag-dosis-angaben","tag-druckpumpe","tag-durchflussmenge","tag-durchflussraten","tag-entkeimungs-kapazitaet","tag-filterung","tag-filterwechsel","tag-fliessgeschwindigkeit","tag-kalk","tag-lampenlebensdauer","tag-mikroorganismen","tag-pha","tag-photolyasen","tag-photoreaktivierung","tag-polyphosphat","tag-strahlungs-dosis","tag-strahlungsleistung","tag-strahlungsquelle","tag-transmission","tag-uv-c","tag-v-c-klaerer","tag-wasser-entkeimung","tag-zellschaden"],"modified_by":"Achim Goerner","_links":{"self":[{"href":"https:\/\/csiag.eu\/en\/wp-json\/wp\/v2\/posts\/1912","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/csiag.eu\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/csiag.eu\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/csiag.eu\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/csiag.eu\/en\/wp-json\/wp\/v2\/comments?post=1912"}],"version-history":[{"count":0,"href":"https:\/\/csiag.eu\/en\/wp-json\/wp\/v2\/posts\/1912\/revisions"}],"wp:attachment":[{"href":"https:\/\/csiag.eu\/en\/wp-json\/wp\/v2\/media?parent=1912"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/csiag.eu\/en\/wp-json\/wp\/v2\/categories?post=1912"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/csiag.eu\/en\/wp-json\/wp\/v2\/tags?post=1912"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}